Docking head for connecting vascular device to a vessel

ABSTRACT

A docking head of the present invention is provided to be mounted on a vascular graft having an outer diameter comparable with the inner diameter of the blood vessel so as to couple the vascular graft to a vessel wall in a suture-less manner. The docking head comprises a thin-walled hollow truncated cone having a passage sized to fit the outer diameter of the vascular graft wherein the cone is capable of connecting to the vascular graft while the hollow thin-walled truncated cone is provided with a plurality of outwardly pointing and inclined plurality of barbs. The docking head act as guiding, anchoring and sealing means between the vascular graft and the vessel.

FIELD OF THE INVENTION

The present invention relates to devices for connecting vascular deviceto a blood vessel. More particularly, the present invention relates to adocking head for vascular device and methods for connecting the same.

BACKGROUND OF THE INVENTION

Aneurysms' ruptures of abdominal aorta are associated with particularlyhigh mortality rates demanding urgent operative repair. Urgent andelective abdominal surgery results in substantial stress to the body,and especially in cases of ruptured aortic aneurysms, the mortality rateis extremely high. There is also considerable mortality and morbidityassociated with elective open surgical intervention to repair aortic,thoracic and aorto-iliac aneurysms. For example, abdominal aneurysmintervention involves penetrating the abdominal wall to the location ofthe aneurysm to reinforce or replace the diseased section of the aorta.A prosthetic device, typically a synthetic tube graft, is used for thispurpose. The graft serves to exclude the aneurysm from the circulatorysystem, thus relieving pressure and stress on the weakened section ofthe aorta at the aneurysm's location.

Repair of an aneurysms and occlusions by surgical means is a majoroperative procedurer. Substantial morbidity accompanies the aneurysmrepair procedure, resulting in a protracted recovery period. Furthermoreand as mentioned herein, the procedure entails a substantial risk ofmortality. While surgical intervention may be indicated and the surgerycarries attendant risk, certain patients may not be able to tolerate thestress of abdominal surgery. It is, therefore, desirable to reduce themortality and morbidity associated with intra-abdominal surgicalintervention.

Anastomosis is the surgical fusion of biological tissues, especiallyjoining tubular organs to create an inter communication between them.Vascular surgery often involves producing an anastomosis between bloodvessels or between a blood vessel and a vascular graft to create orrestore a blood flow path to essential tissues. The first successfulabdominal aortic aneurysm repair involving anastomosis creation wasperformed in 1951.

There are several known method of anastomosis:

One anastomosis method involves harvesting a vein in the body using anartificial conduit made of Dacron, PTFE, PU or other polymers tubing,and connecting the conduit as a bypass graft from a viable artery, suchas the aorta, to the coronary artery downstream of the blockage ornarrowing. A graft with both the proximal and the distal ends of thegraft detached is known as a “free graft”.

A second method involves rerouting a less essential artery, such as theinternal mammary artery, from its native location so that it may beconnected to the coronary artery downstream of the blockage. Theproximal end of the graft vessel remains attached in its nativeposition.

Until about a decade ago, essentially all vascular anastomosis wereperformed by conventional hand suturing. Suturing the anastomosis is atime-consuming and difficult task, requiring much skill and practice onthe part of the surgeon. It is important that each anastomosis providesa smooth, open flow path for the blood and that the attachment becompletely leaks-proof. A completely leak-proof seal is not alwaysachieved on the very first try. Consequently, there is a frequent needfor re-suturing the anastomosis to close any leaks that are detected.The time consuming nature of hand-sutured anastomosis is disadvantageousfor several reasons. First, circulatory isolation and cardiac arrest areinherently very traumatic, and it has been found that the frequency ofcertain post-surgical complications varies directly with the durationfor which the heart is under cardioplegic arrest (frequently referred toas the “cross-clamp time”). Secondly, because of the high cost ofoperating room time, any prolongation of the surgical procedure cansignificantly increase the cost of the bypass or other vascularoperation to the hospital and to the patient. Thus, it is desirable toreduce the duration of the cross clamp time and of the entire surgery byexpediting the anastomosis procedure without reducing the quality oreffectiveness of the anastomosis.

The already high degree of manual skill required for conventionalmanually sutured anastomosis is even more demanding for closed-chest orport-access thoracoscopic bypass surgery. A newly developed surgicalprocedure designed to reduce the morbidity as compared to the standardopen-chest procedure described in U.S. Pat. Nos. 5,452,733 and5,735,290. In the closed-chest procedure, surgical access to the heartis made through narrow access ports made in the intercostal spaces ofthe patient's chest, and the procedure is performed under thoracoscopicobservation. Because the patient's chest is not opened, the suturing ofthe anastomosis must be performed at some distance, using elongatedinstruments positioned through the access ports for approximating thetissues and for holding and manipulating the needles and sutures used tomake the anastomosis. This requires even greater manual skill than thealready difficult procedure of suturing anastomosis during open-chestsurgery.

The biggest drawback of such an anastomosis is that it requires a fairamount of mobility of the two vessel ends to allow easy and accurateplacement of the sutures, and it has a tendency to be constrictive.

In order to reduce the difficulty of creating the vascular anastomosis,there was a need to provide a rapid means for making a reliableanastomosis between a artificial graft or artery/vein and the aorta,native vessels of the heart or other blood vessels. A first approach toexpediting and improving anastomosis procedures has been throughstapling technology. Stapling technology has been successfully employedin many different areas of surgery for making tissue attachments fasterand more reliably. The greatest progress in stapling technology has beenin the area of gastrointestinal surgery. Various surgical staplinginstruments have been developed for anastomosis of hollow or tubularorgans, such as the bowel. These instruments, unfortunately, are noteasily adaptable for use in creating vascular anastomosis. This ispartially due to the difficulty in miniaturizing the instruments to makethem suitable for using in smaller organs such as blood vessels.Possibly even more important is the necessity of providing a smooth,open flow path for the blood. Known gastrointestinal staplinginstruments for anastomosis of tubular organs are designed to create aninverted anastomosis in which the tissue folds inward into the lumen ofthe organ that is being attached. This is acceptable in gastrointestinalsurgery, where it is most important to approximate the outer layers ofthe intestinal tract. However, in vascular surgery, this geometry isunacceptable for several reasons. First, the inverted vessel walls wouldcause a disruption in the blood flow. This could cause decreased flowand ischemia downstream of the disruption, or, yet worse, the flowdisruption or eddies could become a locus for thrombosis that could shedemboli or occlude the vessel at the anastomosis site.

Secondly, unlike the intestinal tract, the outer surfaces of the bloodvessels will not grow together when approximated. The sutures, staples,or other joining device may therefore be needed permanently to maintainthe structural integrity of the vascular anastomosis. Thirdly, toestablish a permanent, nonthrombogenic vessel, the innermost layershould grow together for a continuous, uninterrupted lining of theentire vessel. Thus, it would be preferable to have a staplinginstrument that would create vascular anastomosis that is everted, thatis folded outward, or that creates direct edge-to-edge cooptationwithout inversion.

In recent years, methods have been developed in attempt to treataneurysms without the attendant risks of intra-abdominal surgicalintervention. For example, Komberg discloses in U.S. Pat. No. 4,562,596“Aortic graft, device and method for performing an intraluminalabdominal aortic aneurysm repair” an aortic graft comprising a flexibletubular material having a plurality of struts along its body, to lendthe graft stability and resiliency. The struts have angled hooks withbarbs at their upper ends which are securely attached to the inside ofthe aorta above the aneurysm. Komberg's graft is inserted using atubular device also disclosed in his patent. Komberg, however, onlyanchors the proximal end of the graft. Komberg claims that the downwardflow of blood holds the distal graft securely in place, so that nomechanical attachment is necessary distally. The systolic blood pressurein the abdominal aorta, however, is typically in the magnitude of120-200 mm of mercury (Hg). In spite of the direction of blood flowthrough the graft, proximal to distal, substantial back pressure withinthe aneurysm will result unless the distal end is also mechanicallyattached to the aorta in a manner that prevents substantial leakage ofblood between the graft and the aorta. Without distal attachment, theKomberg's device will not effectively exclude the weakened arterial wallat the site of the aneurysm from the forces and stress associated withthe blood pressure.

Another example can be seen in U.S. Pat. No. 4,787,899 “Intraluminalgraft device, system and method”, disclosed by Lazarus. Lazarusdiscloses a grafting system that employs a plurality of staples mountedin the proximal end of the graft. Lazarus's staples are forced throughthe aorta wall by means of a balloon catheter. Similarly to Komberg,Lazarus uses staples only in the proximal end of the graft. There is noteaching or suggestion as for mechanically attaching the graft to thedistal aorta below the level of the aneurysm or occlusion.

Taheri discloses in U.S. Pat. No. 5,042,707 “Intravascular stapler andmethod of operating same” an articulatable stapler for implanting agraft in a blood vessel. The stapler is in the form of an elongatedcatheter with a plurality of segments mounted on the distal end of thecatheter. The segments have beveled faces and are connected to eachother by hinges. A wire runs through the catheter to the most distalsegment, which is moved, in conjunction with the other segments, into afiring position that is substantially perpendicular to the main catheterbody by the action of pulling the wire. The staple is implanted by usingtwo other wires that act as fingers to bend the staple into itsattachment position.

Taheri, however, appears to be a single-fire design that can onlyimplant one staple at a time. After each staple is implanted, Taheri'sdesign apparently requires that the catheter will be removed beforeanother staple is loaded. In addition, Taheri does not suggest anappropriate density of staples to secure a graft against the pulsativeblood flow of the aorta. Pressures within the aorta range from 120 mm Hgpressure to 200 mm Hg pressure. Without adequate attachment, the graftmay leak around the edges continuing to allow life-threatening pressuresto develop in the aneurysm. Moreover, the graft can even migrate.

Similar inherent defects as the ones referred herein are present inendovascular fastener and grafting apparatus that is disclosed in PCTapplication published as WO 02/17797. Moreover, it appears that someobstacles for blood flow in the vessel evolve from the wire ends. Otherfasteners for the grafts are disclosed in American patent applicationsUS 2003/0176877 by Narciso et al., US 2003/0130671 by Duhaylongsod et aland US 2003/0033005 by Houser et al.

All of the prior references exhibits a need for a sufficiently largesection of healthy blood vessel tissue to ensure the reliable attachmentof the prosthetic graft. The tissue above and below the aneurysm shouldbe long enough for such attachment. The distal part of artery, close toiliac arteries, is usually long enough however the proximal part, calledthe aneurysm neck is not always long enough for attachment of the graftto the vessel wall.

There are number of shortcomings in presently available graft productsand their fixation within the aorta. Although sizing of “tube” or“bifurcated” grafts is radiographically usually assessed prior tosurgery, it is necessary for the surgeon to have a large selection ofgraft lengths and diameters in hand to ensure an appropriate surgicaloutcome.

Additional shortcomings include the placement of a “circular” profilegraft with an associated fixation device within an essentially “ovoid”profile vessel and the use of attachment means that is fasten only tothe insubstantial, structurally compromised (diseased) intima and medialevels of the vessel wall.

Research has exposed yet another problem that indicates that the necksof the post-surgical aorta increase in size for approximately twelvemonths, regardless of whether the aneurysm experiences dimensionalchange. This phenomenon can result in perigraft leaks and graftmigration.

Vascular endoprostheses (stent-grafts) are newly developed surgicaldevices designed to reduce the drawbacks of suturing anastomosisprocedure. The endo-luminal prosthesises were developed about 10 yearsago to avoid major conventional open surgical repair for abdominalaortic aneurysm (AAA). Parodi in 1990 performed the first human stentgraft implantation, backed by extensive animal experiments. In thismethod, incision is made in the patient groin and a catheter is insertedinto a blood vessel that leads to the aorta. A stent graft (usually aDacron tube inside a metal self expandable metal cylinder) is insertedthrough the catheter. Once the stent graft is in place, cylinder isexpanded like a spring to hold tightly against the wall of the bloodvessel. Stent graft can be supplied with the ancure device (EVT/Guidant:ANCURE ENDO-HOOKS). The first production endografts to enter clinicaltrails in the US were approved by the FDA in September 1999 for clinicaluse under a careful monitored training program.

The treatment of AAA with stent grafts is a rapidly evolving field.Several grafts models were introduced (U.S. Pat. No. 6,290,731,6,409,756 are provided herein as references). The stent construction isunique for each type of device. Stents are working in very difficultconditions but there is no knowledge about the long-term durability.Analysis made by G. Riepe et al. (provided herein as references) showsthat the long-term durability of conventional graft is still much higherthen ones of stent graft.

Hence, although in recent years certain techniques have been developedthat may reduce the stress, morbidity, and risk of mortality associatedwith surgical intervention to repair aortic aneurysms, none of thesystems that have been developed effectively treats the aneurysm andexcludes the affected section of aorta from the pressures and stressesassociated with circulation. None of the devices disclosed in thereferences to this patent application provides a reliable and quickmeans to reinforce a diseased artery.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide improved andsimplified system that comprises dedicated devices and methods forsurgically connecting vascular grafts to blood vessels and other holloworgans and especially performing suture-less anastomosis of bloodvessels that may reduce mortality rate, decrease the duration of themost traumatic for patient surgical intervention, drastically shortenthe circulatory isolation and discontinuance of a blood flow path toessential tissues, reduce blood losses, decrease the vessel's trauma andthe frequency, and severity of post-surgical complications.

It is another object of the present invention to provide a new andunique vascular device for anastomosis having a docking head thatreduces the complication of implantation and the high degree of manualskill that is required for conventional manually sutured anastomosis.

It is yet another object of the present invention to provide an improvedmethod of such connection between an artificial vascular graft to thevessel wall in order to decrease anastomosis operation cost due toreduction in the duration of the surgical procedure.

It is therefore provided in accordance with a one aspect of the presentinvention a docking head to be mounted on a vascular graft having anouter diameter compatible with the inner diameter of the blood vessel soas to couple the graft to a blood vessel, said docking head comprising athin-walled hollow truncated cone having a passage sized to fit theouter diameter of the graft and wherein said hollow truncated cone isprovided with a plurality of outwardly pointing and inclined barbs,whereby the docking head act as guiding, anchoring and sealing meansbetween the vascular graft and the vessel.

Furthermore, in accordance with another preferred embodiment of thepresent invention, said hollow thin walled truncated cone is elastic.

Furthermore, in accordance with another preferred embodiment of thepresent invention, said hollow truncated cone has a concaved, convex orstraight profile, sized to correspond to the vessel profile.

Furthermore, in accordance with another preferred embodiment of thepresent invention, said barbs are flexible and are inclined opposite atruncated end of said hollow truncated cone.

Furthermore, in accordance with another preferred embodiment of thepresent invention, some of the said plurality of barbs have a lengththat that is substantially longer than the thickness of the vessel'swall.

Furthermore, in accordance with another preferred embodiment of thepresent invention, said barbs are straight.

Furthermore, in accordance with another preferred embodiment of thepresent invention, some of the said plurality of barbs are bent so as toestablish a concave profile in respect to a radial cross section of saidhollow truncated cone.

Furthermore, in accordance with another preferred embodiment of thepresent invention, some of the said plurality of barbs are bent so as toestablish a convex profile in respect to a radial cross section of saidhollow truncated cone.

Additionally and in accordance with another preferred embodiment of thepresent invention, said hollow truncated cone is provided with aplurality of open slits adapted to allow said truncated cone to curtailits larger diameter.

BRIEF DESCRIPTION OF THE FIGURES

In order to better understand the present invention and appreciate itspractical applications, the following Figures are attached andreferences herein. Like components are denoted by like referencenumerals.

It should be noted that the figures are given as examples and preferredembodiments only and in no way limit the scope of the present inventionas defined in the appending Description and Claims.

FIG. 1 illustrates a cross sectional view of a bifurcated graft inaccordance with a preferred embodiment of the present invention,inserted within an aortic aneurysm.

FIGS. 2-3 illustrate the procedure of opening an access to the aneurysmby a catheter in accordance with a preferred embodiment of the presentinvention.

FIG. 4 illustrates the delivery catheter fixed on top of the aneurysm,ready for insertion of the proximal side of a graft in accordance with apreferred embodiment of the present invention.

FIG. 5 illustrates a cross sectional view of the bifurcated graft shownin FIG. 1, inserted in a proximal neck of the aneurysm in the vesselalong the catheter shown in FIGS. 2-4.

FIG. 6 illustrates a perspective view of the bifurcated graft shown inFIG. 1, passing over catheter tube up to its proximal end.

FIG. 7 illustrates a cross sectional view of the graft shown in FIG. 1in an advanced stage of catheter removal in accordance with a preferredembodiment of the present invention.

FIGS. 8-13 illustrate stages of a tube graft installation in a vesselwith aneurysm in accordance with other preferred embodiments of thepresent invention.

FIGS. 14 a-n illustrate views of various configurations of docking headsin accordance with several preferred embodiments of the presentinvention.

FIG. 15 illustrates an isometric view of graft insertion into aortaguided by a delivery catheter tube in accordance with another preferredembodiment of the present invention.

FIG. 16 illustrates an isometric view of graft positioning using forcepsadapted for outer grasping in accordance with a preferred embodiment ofthe present invention.

FIG. 17 illustrates an isometric view of forceps adapted for innercatching of a graft fastener in accordance with another preferredembodiment of the present invention.

FIG. 18 illustrates the insertion of the graft to the vessel usingforceps shown in FIG. 17.

FIG. 19 illustrates an enlarged view of a docking head in accordancewith a preferred embodiment of the present invention, nailed to thevessel.

FIG. 20 illustrates an enlarged view of a docking head in accordancewith another preferred embodiment of the present invention.

FIG. 21 illustrates a perspective view of a delivery catheter forfacilitating the insertion of a graft in accordance with a preferredembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION AND THE FIGURES

The present invention provides new and unique vascular device forimplantation in hollow organs, especially in blood vessels for treatinganeurysms and occlusions. The new vascular device enables attaching thegraft to the host vessel without the need to suture it; thus treatinganastomosis in a relatively rapid manner. The suture-less anastomosis isperformed in at least one distal side as well as in the proximal side ofthe aneurysm or occlusion so as to accomplish the anastomosis withminimal loss of blood.

According to the anastomosis method provided herein, the vascular deviceis prepared to a required size, blood flow is stopped for relativelyshort while in the sick vessel, blood vessel incision and clearing isperformed and the graft is introduced and installed portions proximallyand distally to the portion of the vessel having an aneurismal orocclusive disease. The non-suture ends connection of the vascular graftto the vessel wall provides leak proof sealing of the connections andrapid blood supply restoration.

The graft is being prepared to fit the required size according to thepatient's vessel dimensions. This is performed prior to the operation.In some of the embodiments disclosed here, modular parts are provided soas to facilitate the leak-proof connection between the graft and thevessel.

In a preferred aspect of the present invention a vascular device isprovided for treating a blood vessel with aneurysm. The vascular devicecomprises a graft, which can be a tubular or have at least oneadditional branch, having a proximal portion and at least one distalportion. A first docking head is provided at the proximal portion and asecond docking head is provided at one of the distal portions. If thegraft is a bifurcated one, both ends of the distal portion are providedwith the docking heads. The vascular device is coupled by the dockingheads to the blood vessel on both sides, above and below the diseasesportion, so as to replace this portion of the blood vessel. The dockingheads act as guiding, anchoring and sealing means in a suture-less andrapid manner.

In another preferred aspect of the present invention, the graft that isprepared prior to the opening of the aneurysm area is longer than thesick vessel portion itself and the docking head that is provided at anend of the graft is mounted so as to allow movement of the docking headalong the end portion of the graft. During the anastomosis, the surgeoncan adjust the docking head or at least one of the docking heads andfasten it or them at the ends of the graft in the required placeaccording to the situation that is revealed after actual opening of theaneurysm. The docking head can be fastened by any of the conventionalmeans such as a fit, glue, suture, clips, staples. Any other techniquefor attaching the docking head in the required place on the graft iscovered by the scope of the present invention.

Reference is now made to FIG. 1 illustrating a cross sectional view of abifurcated graft in accordance with a preferred embodiment of thepresent invention, inserted within an aortic aneurysm. A bifurcatedgraft 10 is inserted within an aneurysm 12 in a blood vessel. Three endsof bifurcated graft 10 are provided with concentric docking heads, afirst docking head 14 at the proximal end and two docking heads 16 atthe distal ends of the graft. Docking heads 14 and 16 are adapted tocouple the graft to the vessel without suturing it and provides thesurgeon with the ability to rapidly connect the graft to the aneurysm.The docking head according to the present invention has three functions:guiding the graft into the vessel, anchoring it into the inner wall ofthe vessel and sealing it so as to provide a continuous wall thatprevents blood from leaking out of the vessel. The procedure ofinserting the graft in the aneurysm is explained herein after.

Reference is now made to FIGS. 2-4 illustrating the procedure of openingan access to the aneurysm by a delivery catheter in accordance with apreferred embodiment of the present invention. FIG. 2 illustrates adelivery catheter 21 that is basically a catheter tube 22 provided witha sharp tip 20 (sharp tip 20 is shown in an enlarged view and act as astylet) that is used to puncture a wall 18 of aneurysm 12 and enterwithin the vessel. Sharp tip 20 is connected to a wire 24 that passesthrough catheter tube 22 and facilitates in its insertion. Sharp tip 20is provided with a withdrawal means 26 at its distal end. As shown inFIG. 3, after the proximal side of catheter tube 22 is within aneurysm12, sharp tip 20 is slightly withdrawn into the catheter's body. Sleeve28 (can be seen clearly in the enlargements in FIGS. 2 and 3) receivessharp tip 20 so that no additional puncturing is performed once thecatheter's proximal side is within the vessel. Catheter tube 22 ispushed further into the vessel so that its proximal side resides withinthe healthy neck portion of the vessel 30. As shown in FIG. 4, afterpositioning the proximal side of delivery catheter 21 within neck 30, alaterally inflatable balloon 32 that is provided in the proximal portionof the catheter is inflated so as to establish a firm hold of cathetertube 22 in neck 30. The surface of inflated balloon 32 is covered withan antifrictional structure which is not cooperating with blood.Delivery catheter 21 is provided with a special tube 34 that extendsfrom its distal side (shown in the enlargement in the Figure) to theballoon in its proximal side wherein liquid can be inserted by a syringe36 into tube 34 so as to inflate balloon 32. Catheter tube 22 providedwith wire 24 is used to guide the graft into the right positioning inthe aneurysm's proximal neck. After the catheter is firmly installedwithin the neck of the vessel and in accordance with a preferredembodiment of the present invention, the graft can be guided onto thedelivery catheter and into the aneurysm.

Reference is now made to FIG. 21 illustrating a perspective view of adelivery catheter for facilitating the insertion of a graft inaccordance with a preferred embodiment of the present invention.Catheter tube 22 is provided with sharp tip 20 that is adapted topuncture the aneurysm as shown herein before so as to enter into thevessel. Sharp tip 20 is connected to the proximal end of the catheterthrough a wire 24 that partially protrudes from the proximal side of thecatheter and its end act also as withdrawal means 26 to withdraw sharptip 20 to within sleeve 28. Wire 24 is adapted to maintain catheter tube22 stiff when it is inserted countercurrent to the blood flow and intothe proximal neck of the vessel. After the balloon is inflated in theneck as explained herein before, wire 24 can be fully removed throughthe catheter's distal end using withdrawal means 26. The deliverycatheter is provided with a side extension 35 adapted to deliver liquidfrom a syringe (not shown in FIG. 21, shown in FIGS. 2-5) that isconnected to the extension through a tubing so as to inflate a balloon(shown in FIG. 21 in an un-inflated position). When wire 24 is withdrawnfrom catheter tube 22, the catheter is fully flexible.

It should be noted that the delivery catheter as disclosed in thepresent invention is adapted to stop the blood flow through theaneurysm's proximal neck when the installation of the graft isperformed. In prior art procedures, the length of the neck is crucial indetermining whether to do the procedure or not, and a relatively shortneck between the aneurysm and the renal arteries will result in avoidingthe procedure all together since there is no possibility to perform sucha long procedure while preventing blood from flowing into the renalarteries. In the procedure disclosed herein, the proximal portion of thedelivery catheter is pushed into the neck and the balloon that isprovided in the proximal portion can be inflated also in a relativelyshort neck. Moreover, the balloon can be also inflated in the area ofthe renal arteries connection or even above them so that the blood tothe kidneys is stopped. Since the procedure of graft implantation inaccordance with the present invention is rapid, the blood flow to thekidneys can be stopped for that short while. Therefore, even an aneurysmhaving a relatively short proximal neck can be treated (FIG. 5illustrates a case in which the blood flow to the renal arteries isbeing blocked).

Reference is now made to FIGS. 5 and 6 illustrating a cross sectionalview and a perspective view of the bifurcated graft shown in FIG. 1,inserted in a proximal end of an aneurysm in the vessel along with acatheter. Since balloon 32 stops the blood from flowing towards aneurysm12, the vessel can be now cut without loose of blood and in order toguide the graft onto catheter tube 22. Bifurcated graft 10 is guidedover catheter tube 22 while the proximal side of the graft 10 isinserted into healthy vessel neck 30 for docking. As mentioned hereinbefore, docking the graft into the neck of the vessel using a dockinghead eliminates the need to suture the graft to the vessel as performedin prior art procedures. The docking procedure is relatively rapid.

In order to firmly and sealingly couple the graft to the vessel, dockinghead 14 is inserted into neck 30. The types of docking head will becomprehensively explained herein after, however, basically, dockingheads 14 and 16 are conical structures provided with a plurality ofinclined barbs 40. Inclined barbs 40 are arranged at the circumferenceof the conical structure in at least one row and are distally pointed tothe direction of the graft's body. The conical structure followed by thegraft is inserted into neck 30 through its narrow end while inclinedbarbs 40 smoothly pass through a portion of the neck. Then, docking head14 is being slightly pulled back. Upon pulling back the conicalstructure, inclined barbs 40 are being imbedded within the neck, forminga firm and sealed connection between the vessel and the graft. Themechanism used in order to anchor the graft in the vessel's inner wallis similar to the mechanism of a bee's sting. Pulling docking head 14backwardly replaces the time consuming suturing procedure that takesplace in the prior art grafting.

Reference is now made to FIG. 19 and FIG. 20 illustrating an enlargedview of docking heads in accordance with preferred embodiments of thepresent invention, nailed to the vessel's inner wall. In FIG. 19, graft400 is provided with a docking head 402, adapted to connect the graft tothe circumference of a vessel 410. Barbs 404 are pointed backward;opposite the direction to which graft 400 is pushed (this direction ismarked by arrow 406). The barbs can be concaved relative to the profileof the graft, convex or partially convex and partially concaved so thatthey can be nailed into the blood vessel wall. Those shapes of the barbsprevent them from contiguously bend on the graft's wall without stickinginto the blood vessel's wall. After positioning of the graft, graft 400is pulled slightly backwardly so as to nail barbs 404 into vessel 410.In FIG. 20, graft 400 is provided with docking head 430 that has aconcaved profile that facilitates its insertion into vessel 410. Dockinghead 430 is provided with barbs that are connected to the docking headin different positions. Barb 432 is connected in a concaved orientationwhile barb 434 is connected in a convex orientation. Different types ofbarbs orientations provide a firm coupling between vessel 410 anddocking means 430 so as to sealingly block any blood leakage from thevessel. The orientations of the barbs also provide firm anchoring of thegraft within the vessel so that there will be substantially no relativemovement between the two.

Reference is now made to FIG. 7 illustrating a cross sectional view ofthe graft shown in FIG. 1 in an advanced stage of graft insertion inaccordance with a preferred embodiment of the present invention. At thispoint, delivery catheter 21 is being removed. Balloon 32 is beingslightly deflated so as to the accord the graft diameter and is beingwithdrawn towards the proximal portion of the graft. The removal ofdelivery catheter 21 allows blood to flow into the graft. In order toprevent blood loose, clip 46 is clamped on graft 10 in an area fromwhich delivery catheter 21 had been already removed. At this point,delivery catheter 21 is being completely withdrawn from within thegraft. The fact that a proximal clip is removed in this stage to thegraft itself is very significant especially in cases in which theproximal healthy neck is relatively short and the renal arteries arebeing blocked. As mentioned herein before, in cases the healthy neck isrelatively short and there is a need to block the renal arteries for theprocedure, the whole procedure is being relinquished since the damage tothe kidneys may be beyond repair. Due to the devices and the methods ofthe present invention, the blockage of blood to the kidneys is for avery short time and there is almost no risk involved in the procedure.The blood flow to the kidneys is restored before the distal docking isperformed.

Reference is being made again to FIG. 1 illustrating a cross sectionalview of the bifurcated graft in accordance with a preferred embodimentof the present invention, inserted within an aortic aneurysm. Bifurcatedgraft 10 is connected in the proximal side to the vessel's neck 30 andis now ready to be connected in its distal side to the two vessels thatbifurcate from aneurysm 12. As mentioned herein before, graft 10bifurcates into two portions in its distal side. Both portions are beingconnected to both vessels in the same way as the connection of the graftto the proximal neck. For that, each bifurcation is provided withdocking head 16 that is basically similar to docking head 14 and is alsoprovided with elastic barbs that are directed towards the graft itself.The connection is immediate and simple while graft 10 is positioned soas to allow docking head to be placed in the healthy distal vessels.Docking heads 16 are pushed into the vessels and than slightly pulledoutwardly so that the elastic barbs are nailed into the vessel andsealingly and firmly connect bifurcated graft 10 to the vessels. Justbefore the actual connection of the distal sides to the vessel, clip 46(not shown in FIG. 1) is removed so as to establish a flow of bloodthrough the graft. After the connection is complete, clips 44 can beremoved so as to establish a blood flow to the blocked areas.

It is important to emphasis again that since the new procedure is arapid one due to the use of docking heads instead of suturing, theblockage of blood to the areas that receive blood through the treatedvessel is for relatively short while. One of the features that may havelethal consequences of any procedure in which aneurysm is treated is theblockage of blood flow through this vessel during the whole operation.One of the major faults of the prior art procedures is the fact that theconnection of the graft to the vessel is extremely time consuming, evenfor a very experienced surgeon. Using the procedures and grafts providedin the present invention markedly reduces the time of operation so thatthe blood is blocked just to a minimum time necessary to dock the graftin the vessel.

Reference is now made to FIGS. 8-13 illustrating stages of graftinstallation in a vessel with aneurysm using a delivery catheter inaccordance with another preferred embodiment of the present invention.In cases the aneurysm is in the upper portion of the aorta, for example,and there is still a healthy portion before the bifurcation of thevessel, one can use a straight graft such as the graft shown herein.According to angiographic results, the graft approximate measures can betaken and a suitable graft can be prepared. Than, midline laporotomy isperformed so as to approach the infrarenal abdominal aorta and exposingthe aneurysm's necks. Vascular clamps are being positioned. FIG. 8illustrates an aorta having an aneurysm 100 in the upper portion. Theprocedure is similar to the procedure described already herein,puncturing the side wall of aneurysm 100 by a catheter 102, positioningit in the vessel's healthy neck 104 and inflating a balloon 106 so as tofirmly maintain catheter 102 for graft guidance. While the aneurysm isbeing punctured by the delivery device, the blood in the proximal neckcan be stopped even with a finger due to the very short act. Vascularclamping is performed in the distal side of aneurysm 100 by vascularclamp 101 and in the proximal portion, by balloon 106. The size of thegraft is being evaluated again and fixed to suit the size of aneurysm.Then, an incision in the side wall of the aneurysm is performed as wellas suctioning the blood residuals so as to allow a graft 108 to bemounted onto delivery catheter 102 (incision 103 is shown in FIG. 10).Similarly to bifurcated graft 10, graft 108 is provided with dockingheads. A first docking head 110 is provided in the distal end of graft108 that is being guided onto catheter 102. Docking head 110 is advancedinto neck 104 and then pulled back so as to nail the flexible barbs intothe wall of the proximal neck.

After the proximal end of graft 108 is firmly secured within neck 104,balloon 106 is slightly deflated so as to allow its withdrawal throughgraft 108 as shown in FIGS. 9 and 10. Catheter 102 is withdrawn and aclip 112 is clipped onto graft 102 so as to stop blood flow. The distalportion of graft 108 is free to be docked into the distal neck of thevessel. Docking head 114 is inserted into the aneurysm and positionedwithin the distal healthy neck 116. Again, due to the elastic barbsprovided on docking head 114, its connection to the neck is very quickand firm by advancing the docking head forward and then slightlywithdrawing it backwardly so that the barbs are nailed into the neck.Vascular clamp 101 can be removed so as to restore blood flow to theportions of the body that receives blood from the vessel. FIG. 13 showsthe vessel after incision 103 is sutured. This procedure can beperformed also using another delivery device other then a deliverycatheter as will be shown herein after.

Reference is now made to FIGS. 14 a-n illustrating views of variousconfigurations of docking heads in accordance with several preferredembodiments of the present invention. The docking heads shown herein areadapted to connect the graft within the vessel in a suture-less mannerso as to establish a firm and secured connection as well as a connectionthat fully seals the vessel so as to ensure that there is no leak ofblood through the connections. Generally, the docking heads are hollowthin-walled elastic truncated cones that are mounted onto the end of thegraft. The small diameter end of the cone is fitted to the externaldiameter of the vessel and the bigger diameter surpasses it for about1-10 mm. The cones can be concaved as shown in embodiments g, h, l, andm so as to facilitate its insertion into the aneurysm's neck; however,they can be straight as in a-f or convex. The cones are providedpreferably with elastic barbs on the cones external surface. The barbsare inclined relative to the cone and are directed to the direction ofthe graft's body. It is preferable that the length of the barbs will notexceed the thickness of a wall of the vessel so as to prevent puncturingthe vessel.

In FIGS. 14 a-d, the docking head is a conical structure 150, 150′, 150″and 150′″, respectively. The conical structure can be of relativelyshort length (150) or longer (150″), depending on the length of thehealthy portion of the neck in which it has to be coupled. The conicalstructure is provided with a plurality of barbs 152 that are adapted tonail into the neck at the edges of the aneurysm. Barbs 152 arepreferably flexible. It is shown in embodiment d that the cone isprovided with slits 151 that enables the cone to curtail from its outerdiameter when it is introduced into the neck so as to facilitate itsinsertion. The slits can be of about 0.3-0.6 cm.

FIG. 14 e and illustrate conical structures 154 that are produced byoutwardly everting the end of the graft's body so that the truncatedcone is an extension of the graft. The truncated cone is provided withbards 156.

Modular docking heads are shown in FIGS. 14 f-h and 14 k-n. Themodularity of the docking head provides the device with versatility sothat the surgeon can decide in any stage of the operation which dockinghead to use. A truncated cone 170 is mounted on the edge of graft 172and is connected to it by a connector 174. The advantage in these typesof docking heads is that the type can be chosen of a plurality ofdifferent types even during operation when the surgeon can adapt theright cone that suits the inner structure of the particular vessel. Thelength of the cone as well as its angle can be different. The surgeoncan prepare in advance an elongated graft having a stable docking headin the graft's proximal end and a modular docking head that is slidablyprovided in the distal portion of the graft. After the surgeon docks theproximal docking head of the graft in the proximal neck, he may measurein real time the actual length of the graft and stabilize the slidabledistal docking head in a suitable place while the residual graft can becut. In any of the embodiments, plurality of barbs is provided on eachone of the cones.

Reference is now made to FIG. 15 illustrating an isometric view of graftinsertion into aorta guided by a delivery device in accordance withanother preferred embodiment of the present invention. Since theprocedure in accordance with the present invention is very quick andthere is a desired to stop the blood flow to the organs for a minimumamount of time, the proximal portion of a vessel 200 can be clipped witha vascular clamp 202 so as to stop the blood flow to the aneurysm area.An incision 204 is performed in the aneurysm area while a finger 206blocks the proximal side of the vessel. Alternatively; another vascularclamp can be used in order to block the proximal side. A guide 208 isinserted into the proximal portion of vessel 200 while a graft 210 ismounted on guide 208. After the positioning of the guide in the healthyneck in the proximal side of the vessel, the proximal side of graft 210is placed within the corresponding neck while pulled slightly outwardlyin order to nail barbs 212 of docking head 214 in the distal neck. Guide208 is then removed and the proximal portion of graft 210 is insertedwithin the vessel. Docking head 216 that is connected to the distal sideof graft 210 is placed within the distal portion of the healthy vessel'sneck while pulled slightly outwardly in order to nail bards 218. Theblood flow then can be restored.

Eliminating the need to suture the graft to the proximal and distalportions of the vessel enables a rapid procedure and offers the use ofmany other delivery devices so as to implant the graft into the vessel.

Reference is now made to FIG. 16 illustrating an isometric view of graftpositioning using forceps in accordance with a preferred embodiment ofthe present invention. Similarly to the previous procedure, blood isstopped using vascular clamp 250. A clip 252 is also put on the distalside of the vessel. An incision 254 is performed in the aneurysm and agraft 256 is positioned within the proximal portion of the vessel usinga forceps 258 with jaws. Graft 256 is held and positioned within thevessel using forceps 258 having its jaws inserted between docking head260 conic structure and the graft itself so as to gain control on thepositioning of the graft's proximal side. The proximal docking head 260is placed and nailed to the vessel's proximal portion. Forceps 258 areremoved from the proximal portion of the vessel and then can be used inorder to connect the distal side of the graft.

Reference is now made to FIG. 17 illustrating an isometric view offorceps adapted for inner catching of a graft in accordance with anotherpreferred embodiment of the present invention. Forceps 300 are designedwith jaws 302 that are adapted to guide a graft 304 into the vessel.Jaws 302 have an elongated and curved body 301 and rounded and pointedhead 303 at its edge. Elongated and curved body 301 is adapted to bethreaded within graft 304 and rounded and pointed head 303 is designedto accord the inner diameter and shape of the edge 306 of graft 304.

Reference is now made to FIG. 18 illustrating the insertion of the graftto the vessel using forceps shown in FIG. 17. Vessel 308 is clipped byclips 310 as described herein before, proximally of an aneurysm anddistally of it. An incision is made so as to insert the graft. Graft 304is mounted onto jaws 302 while rounded head 303 partially protrudesbeyond the graft, guiding the way to the proximal portion of the vessel308. Using forceps 300, the surgeon directs docking head 312 into thehealthy proximal portion of vessel 308 and couples it in the methoddescribed herein before. Then, the distal side can be coupled in thesame manner.

It should be clear that the description of the embodiments and attachedFigures set forth in this specification serves only for a betterunderstanding of the invention, without limiting its scope as covered bythe following Claims.

It should also be clear that a person skilled in the art, after readingthe present specification can make adjustments or amendments to theattached Figures and above described embodiments that would still becovered by the following Claims.

1. A docking head to be mounted on a vascular graft having an outerdiameter, said docking head comprising substantially non-extendablethin-walled hollow truncated cone having a passage sized to fit theouter diameter of the vascular graft and wherein said hollow truncatedcone is provided with a plurality of outwardly pointing and inclinedbarbs, wherein said docking head is connected to the vascular graftbefore its coupling to a vessel and act as guiding, anchoring andsealing means between the vascular graft and the vessel.
 2. The vasculargraft as claimed in claim 1, wherein the vascular graft is tubular,bifurcated or has at least one additional branch.
 3. The docking head asclaimed in claim 1, wherein a portion of said thin-walled hollowtruncated cone is elastic.
 4. The docking head as claimed in claim 1,wherein a portion of the said docking head is cylindrical.
 5. Thedocking head as claimed in claim 1, wherein said thin-walled hollowtruncated cone has a concaved, convex or straight profile, and whereinthe vessel's profile corresponds to the cone profile when the dockinghead is coupled to the vessel wall.
 6. The docking head as claimed inclaim 1, wherein said barbs are flexible and are inclined opposite atruncated end of said hollow truncated cone.
 7. The docking head asclaimed in claim 1, wherein some of said plurality barbs are sized to alength that is substantially longer than the thickness of a vessel'swall so as to enable perforation of the vessel's wall.
 8. The dockinghead as claimed in claim 1, wherein said barbs are straight.
 9. Thedocking head as claimed in claim 1, wherein some of the plurality ofbarbs are bent so as to establish a concave profile in respect to aradial cross section of said thin-walled hollow truncated cone.
 10. Thedocking head as claimed in claim 1, wherein some of the plurality barbsare bent so as to establish a convex profile in respect to a radialcross section of said thin-walled hollow truncated cone.
 11. The dockinghead as claimed in claim 1, wherein said hollow truncated cone isprovided with a plurality of open slits adapted to allow said truncatedcone to curtail its larger diameter.
 12. The docking head as claimed inclaim 1, wherein said thin walled truncated cone is connected to thevascular graft, wherein the vascular graft is outwardly everted over aguiding end of the said docking head for fixating the graft on thedocking head.